Greywolfe

Hey guys I need you opinions. I have a humming noise that starts up at about 50 mph coming from the rear of my C5. I think its my drivers side rear wheel bearing but I am not sure.

I lifted the car and tried to rock the wheel from top to bottom and left to right and everything is tight so I'm thinking it might not be the bearing.

I took the car out on the road and got up to 55 mpg and depressed the clutch and still had the noise. I then did some slalom turns (like warming up tires) to tranfer wieght from side to side. When I turned to the left the noise went away, when I turned to the right the noise got louder and when driving straight it was half way in between.

So I think its the drivers side rear wheel bearing but before I spend time and money changing it I would like your opinions.

Thanks in advance.

drivinhard

Hoosier A6's strike again

davidfarmer

do you have any aftermarket brake ducts, or anything else that could be scraping??? I recently had a similar issue, and it was my ducts. Have you jacked it up and checked for play in the bearing as well??

UstaB-GS549

I had a left front bearing that was humming. No detectable play with wheel off the ground, but I replaced it anyway and the noise went away.

If you take the wheel & rotor off, check the flange on the bearing hub for cracks.

Bill Dearborn

I had a similar problem on my 97. I could hear a humming sound but could not place where it was coming from. Since it was under GMPP the first replacement was the right front. The humming was still there but lower, the second replacement was the right rear and the humming got lower yet. Finally both the other bearings were replaced and the humming went away. None of these bearing was loose. The mechanic who replaced the right front told me he guessed at it and could only tell the bearing was bad when he had it off the car and in his hands and could feel the roughness as he turned it.

Bill

Jason

FYI, Autozone warranties bearing hubs for 1 year.

It's worth the time and trouble to keep the wheel attached to the car, especially at RA. Take your best guess and do that one first. Keep working around till you find it.

longdaddy

My fronts were making nasty noise but still felt tight. I think the point at which you start to be able to rock them is the final stage before catastrophic failure.

bobmoore2

That's the same list of symptoms I had on my C5 a couple years ago, except mine was on the other side (right rear). After they replaced that hub, everything was back to normal again.

Replacing your left rear hub is your best bet.

waddisme

I picked up a spare one to take to track in case one went out. But thinking about it, it seems like a lot of work to do at the track. Would you guys attempt it?

bobmoore2

I would not attempt to change a hub myself at the track, mainly because I don't know how difficult it would be.

However, I think it is a good idea to carry one with you to the track. Then if one fails, you can go to a repair shop in the nearest town and know the replacement part will be available.

Greywolfe

Thanks alot for all the responses. I'm going to go ahead and replace the hub assembly. I'll let you know if the noise goes away.

The car is 100% stock with the exception of track pads. (I know I need to get cooling ducts among a long list of other things).

Mark. I only ran on those A6's one weekend at CMP in Feb. I have been on my street tires on my last 3 events as my tires are stuck up in Shelby, NC.

Jason

I carry a spare since I lost a full day a few years ago. I'd change them in the paddock on Saturday, on Sunday I'd probably put it on the trailer.

JohnD60

My experience is similiar to the rest. The fact that the sound is different in left and right turns certainly points to the bearing.

I also carry a spare since I've lost a whole weekend due to failure as well. Even if you don't want to do it yourself, sometimes the track tire support will change out a bearing if you have the part (at least this was the case in my situation before i started carrying a spare).

John

Wayne O

I just came from running at Inde Motorsports Ranch (a great new racing facility near Willcox, Arizona) this past weekend and experienced something very similar with my C6. I'm hearing a 'harmonic' noise when making hard right turns. No noise when turning to the left though. I checked all the tires and front and rear brake ducts (SCAT hoses). There isn't any 'slop' in the wheels but a couple hubs aren't spinning as smoothly as I'd like. I'm sure it's a wheel bearing.

SIK02SS

I think the power steering pumps are lifetime...need to check my receipt to be sure though

longdaddy

This is exactly how mine started. Look for noise to gradually get louder and you will eventually start hearing it under braking.

R Mackow

A failed front bearing will make a "shhh" noise when driving straight ahead then making slight left or right steering adjustments. At this point your caliper bracket is probably holding the wheel on. Look for what looks like metal filings laying on the inside of your wheels. Take off the rotor and check the stud flange/hub connection. It may be completely seperated.

Rear hub failure has the same symptom, a shhhh sound. It means your rear rotor is contacting the outboard face of the aluminum control arm. Look for s shiney spot on the lower control arm.

Use a real ball joint seperator, not a pickle fork. Remove the entire assembly that the hub is bolted to. Use a one piece T-55 driver. The two piece socket is a piece of sh*t. Torque on these torx head bolts is pretty high. The rear ball joint in the lower control arm needs a low profile allen head wrench.

If you are not experiencing an mechanical obvious failure of metal parts between hub and flange, check this area for a rusty fracture line, which would indicate immenient failure. Spin the bearing. I should have some resistance, but turn smoothy and quitely.

I've never change on at the track...yet.

Greywolfe

Alright. I got the hub assembly changed out. I ordered a Timkin from Azone. Came in a Timkin box and said made in the USA on it.

That was definately the problem. Now there is no more noise and the car seems to be driving super smooth. All I hear is exhaust sound now .

It wasnt too bad of a job but I would not want to have to do that at the track in 100 deg heat.

WBHighwind

Is there a life expectancy for these things? Ive had my car for 2 years and done at least 15 track days and put 10k miles on it, should I be considering changing them out? Im in the process of getting my car ready for RA in two weeks.

Greywolfe

Lift the car so the wheels are off the ground and then grab the tire at the top and bottom and try to rock it. There should not be any play.

Also if they start making noise or vibrations they are starting to go. If you have no play and no noise then you should be fine.

I have 60K on the car and started DE in the summer of 2008. I have around 10+ weekends of DE under my belt and I just replaced my first wheel bearing. DE1 and DE2 wasn't too hard on the car. Now that I am pushing harder I expect them to wear out faster.

I'm sure the guys doing this longer than me can give better feedback but they will wear out faster with hard track use. Maybe one season out of a set as I have read in other posts. Then its time to go with the SFK racing hubs.